<template>
        <li>
            <label>
                <input type="checkbox" :checked="todo.done" @change="handleCheck(todo.id)"/>
                <!-- input type="checkbox" v-model="todo.done" 不能这样写,因为改变了props中传入的数据 -->
                <span v-show="!todo.isEdit">{{todo.title}}</span>
                <input v-show="todo.isEdit" 
                type="text" 
                :value="todo.title"
                @blur="handleBlur(todo,$event)"
                ref="inputTitle"
                >
            </label>
                <button class="btn btn-danger"  @click="handleDelete(todo.id)">删除</button>
                <button v-show="!todo.isEdit" class="btn btn-bianji" @click="handleEdit(todo)">编辑</button>
        </li>
</template>

<script>
    import pubSub from 'pubsub-js';
    export default {
        name:'MyItem',
        //声明接收todo对象
        props:['todo'],
        methods:{
            //获取改变的todo的id 将id传给App
            handleCheck(id){
                // console.log(id)
                //通知App组件将对应的对象done取反
                // this.checkTodo(id)
                this.$bus.$emit('checkTodo',id)
            },
            handleDelete(id){
                if(confirm('确认删除啊吗？')){
                    // this.deleteTodo(id)
                    // this.$bus.$emit('deleteTodo',id)
                    pubSub.publish('deleteTodo',id)
            }   
            },
            handleEdit(todo){
                // todo.isEdit = true
                if(todo.hasOwnProperty('isEdit')){
                    todo.isEdit=true
                }else{
                this.$set(todo,'isEdit',true)}
                this.$nextTick(function(){
                    this.$refs.inputTitle.focus()
                })
            },
            //失去焦点后真正修改
            handleBlur(todo,e){
                todo.isEdit = false
                // console.log('updateTodo',todo.id,e.target.value)
                if(!e.target.value.trim()) return alert('输入不能为空')
                this.$bus.$emit('updateTodo',todo.id,e.target.value)
            }
        }
    }
</script>

<style scoped>
    /*item*/
    li {
        list-style: none;
        height: 36px;
        line-height: 36px;
        padding: 0 5px;
        border-bottom: 1px solid #ddd;
        }

        li label {
        float: left;
        cursor: pointer;
        }

        li label li input {
        vertical-align: middle;
        margin-right: 6px;
        position: relative;
        top: -1px;
        }

        li button {
        float: right;
        display: none;
        margin-top: 3px;
        }

        li:before {
        content: initial;
        }

        li:last-child {
        border-bottom: none;
        }
        li:hover{
            background-color: #ddd;
        }
        li:hover button{
            display: block;
        }
        
</style>